SQL Injection in Croixhaug Appointment Booking Calendar — Simply Schedule Appointments Plugin

CVE-2026-1708

The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to blind SQL Injection in all versions up to, and including, 1.6.9.27. This is due to the `db_where_conditions` method in the `TD_DB_Model` class failing to prevent the `append_where_sql` parameter from being passed through JSON request bodies, while only checking for its presence in the `$_REQUEST` superglobal. This makes it possible for unauthenticated attackers to append arbitrary SQL commands to queries and extract sensitive information from the database via the `append_where_sql` parameter in JSON payloads granted they have obtained a valid `public_token` that is inadvertently exposed during the booking flow.

Vulnerability class: SQL Injection

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (32.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-1708: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-1708?
CVE-2026-1708 is a high-severity vulnerability in Croixhaug Appointment Booking Calendar — Simply Schedule Appointments Plugin, classified under SQL Injection. CVSS score: 7.5/10. Published 2026-03-11.
How severe is CVE-2026-1708?
High severity. CVSS v3 base score is 7.5 out of 10.